In any% runs, yeah. But they skip through all the dialogue and cutscenes anyway, so it's barely spoilers. Most of the speedrun is just crazy hops and killing Shadowheart to stuff her corpse in a crate.

AGDQ did an actual all acts speedrun, which does show the actual ending of the game though. And admittedly, more spoilery than a usual run because there's a lot of commentary.

If it's a normal any% speedrun (I assume so) then it will yeah.